from Dr. Thornton. 533 



** Tu the first column are the names of the fluids ; in the 

 second, the heights to which they rose in one and the same 

 glass pipe; in the third, the densities of the fluids; and in 

 the fourth, the weisihts sustained by the same pipe. 1 ob- 

 tained the weights by mukiph/iug the heights into the den- 

 sities : for the weights of cyUaders are as their magnitudes 

 and densities taken together, or as their heights and densi- 

 ties t'lken together if their bases be equal ; but the oases of 

 all the eyUnders of different fluids sustained by one and the 

 same pipe are equal, and therefore the weights of such cy- 

 linders are as their heights and densities taken together. 



*' Hence it appears that one and the same glass pipe at- 

 tracts diflerent fluids with different degrees of force. It at- 

 tracts spirit of vitriol more strongly than oil of vitriol, oil 

 of vitriol more strongly than water impregnated with salt, 

 water impregnated with sal gem and nitre more stron&ly 

 than con)mon water cold ; conuiron water cold, more strongly 

 than the animal fluids and common water made boiling hot; 

 ^he animal fluids more strongly than fermented liquors ; 

 fermented liquors more strongly than oils ; and oils more 

 strongly than ardent spirits. 



"^ -So then, if equal quantities of all the fluids of this 

 table were mixed together, the same glass pipe \^'ould suck 

 in different parts of this heterogeneous fluid in different pro- 

 portions. It would suck in more parts of water nnpreg- 

 jiatcd with salt than of oil or ardent spirits. The parts least 

 attracted would be driven off", to make way for those which 

 are most attracted to enter into the pipe ; as in a fluid v.here 

 the force of gravity alone takes place, the lighter bodies are 

 forced to ascend, to make w ay for the descent of bodies 

 which are heavier. 



^' 3ir Isaac Newton has proved from experiments, that 

 the particles of light attract ardent spirits and oil more 

 strongly than water; aiicl by consecjuence, if we suppose a 

 small pipe to be formed out of particles \\hose attracting 

 powers are the same with those of the particles of light, and 

 one end of it to be dipped into a heterogeneous fluid com- 

 posed of equal quantities of all the fluids of this table inti- 

 mately mixed together, such a pipe would attract the parts 

 of oil and ardeiit spirits more strongly than those of water, 

 and suck in more parts of the two former than of the latter. 

 The fluid, tlureforc, drawn out of the heterogeneous fluid 

 by this pipe, v.ould be different from the fluid drawn out of 

 it by a small glass pipe; for tv.o fluids will be different, 

 when they cither consist of different parts, or of the same 

 parts mixed indifferent proportions. 



" Now, 



